Roofers in North Mundham

1.1 How lead goes wrong

Lead fails at its edges. It lifts where the mortar that holds it has crumbled, it splits where it was folded too tightly, and it slides when it was never held by clips along its lower edge. Leadworx calls Code 4, a sheet 1.80 mm thick, the everyday lead for general flashings, and sets Code 5 against larger runs and vertical faces. Code 3 is recommended for soakers only, the small folded pieces slipped under each tile or slate at a wall. MyJobQuote puts a well-made lead flashing at 80 years and beyond, and 100 for the heavier codes, so a failure on a roof of ordinary age usually means a poor joint rather than tired metal. Our lead roofing page covers the detail work.

1.2 Chimney stacks and flaunching

Flaunching is the sloping mortar bed that holds a chimney pot in place and sheds rain away from its base. When it cracks, water runs into the stack and shows as damp on a chimney breast two floors down. We look at the flaunching, the pointing, the lead tray or back gutter behind the stack, and the pots themselves. MyBuilder gives a typical UK range of £500 to £2,000 for repointing a chimney, with around £750 as a middle figure, and MyJobQuote gives £150 to £250 for patching a lead flashing. The right price for your stack comes after the survey. Our chimney repairs page explains the stages.

3.1 Falls and ponding

Water on a flat roof has to run somewhere. IKO, citing BS 6229:2018, recommends a minimum fall of 1:80 and says to design for 1:40 to leave room for building tolerances and deflection. Standing water that lingers after rain, known as ponding, usually means the fall has gone. Laying a new covering over a failed deck seldom cures that, which is why we look beneath the surface before quoting. Our flat roofing page sets out the options.

3.2 Insulation when a flat roof is re-covered

Under Approved Document L, a fresh waterproof layer is classed as renovation of the roof's thermal element, and once more than 50% of the surface is renewed the whole element has to reach the upgraded standard. For a flat extension that usually means insulation to current standards goes in with the new covering, which can raise the finished level at doors and walls. We note the upstand heights at the survey, so the surprise does not arrive on the day.

3.3 Older garages and sheds

HSE's advice for a building put up or refurbished before 2000 is to presume asbestos is present. Asbestos cement roof sheeting, carefully removed without breaking it up, is non-licensed work, but substantial breakage makes it notifiable. Waste is double-wrapped, labelled and consigned properly, never tipped into an ordinary skip. HSE also asks whether sound sheets could stay in place under a new, asbestos-free covering.